POWER AND POLLUTION Battery car’s future far from rosy

Press, Volume CXI, Issue 32589, 24 April 1971, Page 13

POWER AND POLLUTION Battery car’s future far from rosy

A source of pollution—although how major is still open to considerable dispute—is the petrolburning internal combustion engine without which much of the world would come to a halt. Electric cars—and presumably ambulance, fire appliances, police vehicles, utility vehicles and public transport—have been widely suggested as one solution. But a close consideration of the electric-car question shows the problems to be great, the repercussions and implications widespread, and the prospects of success slim.

The Post Office in Britain is experimenting with electric vans, the Swedish Government is doing the same, Russia is considering the production of a million electric commercial vehicles, and electric buses are being tested in the United States, Britain and Germany.

All these applications demand batteries. In Britain there are 250,000 battery lawnmowers, golf buggies in the United States use 100,000 batteries a year, and other ,uses of battery-stored electricity include invalid cars, wheel-chairs, garden tractors, and emergency and camping lighting equipment.

An authoritative view on batteries was given in Wellington early this month by Dr M. Barak, expatriot New Zealander for 45 years, research expert and scientific adviser for Britain’s Chloride Group, and internationallyrecognised authority on storage batteries.

Battery problems Dr Barak’s visit was sponsored by the Australian Lead Development Association, and the emphasis was, not surprisingly, on the lead-acid battery.

But Dr Barak had plenty of technical evidence to back him when he plumped for the lead-acid battery as the practical power-storage unit of today.

And he made no bones about the prospects for other types of battery: “I cannot see any of the experimental batteries taking the place of the lead-acid battery in any way for at least 10 years.”

Batteries such as the sodium-sulphur and lithiumchlorine units had major disadvantages which put them out of court for practical purposes, in spite of their theoretical advantages, he said.

Like other experimental batteries, they could be dangerous and difficult to use and make.

The sodium-sulphur battery, for example, had to be heated to 350 degrees Centigrade before it would work —for the lithium-chlorine unit this figure was 650 degrees. “So in a car, if you went into a pub and let the battery cool down —and knowing the drinking reputation of New Zealanders, this could happen —you would not be able to get started,” he said. What Dr Barak had to say did not paint a rosy picture for the' future of the practical electric car, one of the main objections to which, he said, was the limited range of 50 or so miles.

90001 b of batteries

In contrast there are possibilities for electric buses. The M.AN. company in Germany is now testing its “elektrobus, which tows behind it a 90001 b battery-trailer that is exchanged every three hours for a trailer with recharged batteries.

The vehicle’s top speed is 37 m.p.h., it is smooth, fumeless, and silent, acceleration is on par with other buses, and operating costs are claimed to be lower than with a conventional vehicle.

The only practical battery for such applications, now and in the forseeable future, was the lead-acid type, Dr Barak indicated. This was on the grounds of cost, rechargeability, safety, storage characteristics ana ease of manufacture.

But as the state of the art is at present—and there are no indications of' any great

(By A. ]. PETRE)

change—lead-acid batteries cannot be reduced markedly in size and weight. Aspects of the battery which cannot be changed to any degree are the size and weight of the active material plates or tubes, of the conductive grid which supports the active material, and the quantity of the electrolyte. This leaves only the nonreactive parts of the battery to work on: the cell box separators, the top lead, and the negative grid. This is only 25 per cent of the battery by weight, and less by size.

On the brighter side, engineers have succeeded in reducing the size and weight of these components—plus the battery case—and in getting about a third more energy from a battery of any given size in the last 20 years or so.

Battery charging

But this still leaves the situation where any batterypowered car built with present knowledge and technology would have a great deal of space taken up by heavy batteries, low speed, short range, and long recharging time. Using normal methods, charging the batteries—end lead-acid batteries can be recharged up to 2000 times, which is far from the case with most alternatives—will take about eight hours. Using the latest fast-charging gear, this can be reduced to five hours.

An American researcher had developed a battery-car which could be recharged, he claimed, in about 30 minutes, Dr Barak said. But this required a special high power supply, and rectifying equipment worth about $2OOO. The aim had to be to develop some sort of battery vehicle which could be recharged from the mains, he said. In Japan, a manufacturer was making 100 electric cars a month. But they had a top speed of 40 m.p.h. and a range of only 40 miles, recharging taking at least eight hours. A question Dr Barak’s papers raised in the minds of at least some of his listeners was whether a mass swing to electric cars, as technical knowledge stands at present, might not merely be exchanging one sort of pollution for another.

Power demands

If thousands of cars were to be recharged from the mains, and they would not all be recharged only at night, presumably extra demands would be placed on national power-generating resources. And in many countries, notably the United States, national power-generating resources are already stretched to their limit, with demand still rising steeply. In many of these countries, again, extra generating capacity can be gained only by more power stations, which must be fuelled either by fossil fuels—coal or oil—or nuclear fuel. Coal and oil-burning stations produce air pollution, so they are obviously “out” But nuclear stations produce thermal pollution and the threat of radiation pollution from that hard-to-hide radioactive waste.

With the prospect of relatively “clean” internal combustion engines within a few years—current United States regulations call for almost completely clean car exhausts in the next 10 years, and this is said to be technically possible if expensive to deveiop-7-should nations exchange air-pollu-

tion for thermal and radiation pollution, and at considerable cost?

Cooling towers may overcome much of the thermal pollution problem (albeit at even more cost) but the disposal of radioactive wastes is still a vexed question.

One might argue that countries like New Zealand which have hydro-electric generating capacity can indeed obtain power without pollution. But it could also be said that wholesale damming of lakes and rivers to obtain this power is in itself a form of pollution—scenic pollution, if you will—and as such, undesirable.

Until mankind can efficiently harness the power of the sun or the tides, there seems no way of obtaining power without pollution in one of its forms. And so far, efforts with tidal power generation and solar cells have met with very limited success.

If one adds to all this

consideration of the world’s dwindling reserves of such fuels as oil and coal, there would seem to be every reason for thinking civilisation is rapidly approaching an era of power crisis: a view which more than a few leading scientists would share.

Practical problems

The electric car, which started all this, has notable practical problems of its own, One is economic: one could only sell electric cars at the same sort of price as today’s internal-combustion cars if one could produce them in the same numbers.

And one could not produce them in the same numbers unless one could sell them at a competitive price. And even at a competitive price, who would want to pay $2OOO or more for a small car with a range of no better than 40 miles and a top speed of 40 m.p.h. between eight-hour recharges? A really practical all-pur-pose electric car would nave to be a four to five-seater capable of cruising for at least 200 miles at up to 80 m.p.h. between charges. Then one could stop at a service station—as one now does for petrol—and exchange the discharged battery for a fresh one.

But this predicates a reasonably small, compact and easily removed batterypack for a start, plus a nation-wide chain of chargerequipped service stations. Then there are the practical problems which appear minor at first sight, but more difficult on closer scrutiny. Take heating, for example: how would you rig a heater in a batterypowered car? Would the battery be man enough to provide sufficient power for running the vehicle plus its heater, lights, and radio? Efforts to increase batterycar range and practicality by using petrol engine-electric hybrids, and electric drives which consume power when driving and boost the battery under deceleration and braking, have produced very mixed results at best It is impossible to escape the law of' nature that you don’t get something for nothing, and usually lose something in overcoming friction, inertia, and windresistance. As Dr Barak said, the leadacid battery plainly has a considerable future Tn modem life; for some vehicles, emergency lighting, starting engines, aiding communications, and so on. The wider implications of his remarks are even more interesting: it is impossible to consider any change in our uses or production of energy without also considering the effects in other fields. One cannot deal with each aspect in isolation. Which is, when you think about it, what much of the campaign against pollution is really ail about.